As can be appreciated by those of skill in the art, it is common for a wrist fusion apparatus such as a plate to be used in arthrodesis to fuse bones of the wrist area of a patient in a desired orientation. A variety of configurations and designs of wrist fusion plates exist within the prior art for utilization in this manner.
It is common for some types of wrist fusion apparatuses to extend typically from the radius to a metacarpal, such as the third metacarpal, of the hand for utilization in wrist fusion. Wrist fusion apparatuses of this variety are typically fastened both to the radius and to the third metacarpal by bone screws, and wrist fusion apparatuses of this variety also therefore overlie the carpus area and the bones of the carpus area which are positioned between the radius and the metacarpal bones. As known to those of skill in the art, bone grafts can be packed between the radius, the carpus area bones, and the metacarpals after such a wrist fusion plate is in place, and the bone grafts typically will bond with the adjacent bones in order to create a fused bone mass at the wrist joint.
U.S. Pat. No. 5,853,413 to Carter et al. discloses such a wrist fusion apparatus in the form of a plate configured to extend over the carpus area and to position at least one metacarpal relative to the radius. A saddle portion is included in the wrist fusion plate and is placed over the carpus area. A proximal end extends from the saddle portion and is attachable to the radius, while a distal end extends from the saddle portion and is attachable to one of the metacarpals. The proximal end extending from the saddle portion defines a first longitudinal axis, and the distal end extending from the saddle portion defines a second longitudinal axis wherein the first and second longitudinal axes are not actually aligned in a medial-lateral direction.
Generally, the use of a dorsal wrist fusion plate is indicated in patients with post-traumatic or degenerative wrist arthritis, conditions involving significant loss of bone substance, and failed total and partial wrist arthrodesis. Wrist arthrodesis can also be successfully utilized in patients with complex fractures of the wrist. A fusion plate can be utilized in patients with rheumatoid arthritis, although simpler stabilization techniques are currently fairly predictable. Contraindications to utilizing a metacarpal sparing total wrist fusion plate involve severe carpal bone loss requiring stabilization to the metacarpal to maintain alignment and stability and evidence of active ongoing infection at the time of the surgical procedure.
Wrist fusion plate apparatuses and methods such as that disclosed in Carter et al. require attachment of a portion of the wrist fusion plate to one or more of the metacarpals of the hand. Unfortunately, this feature suffers various undesirable disadvantages, such as a high propensity for the development of extensor tendinitis at the prominent distal end of the plate necessitating removal of the plate and a second surgical procedure.
Despite the prior art wrist fusion apparatuses and methods, there remains much room for improvement in the art, particularly for a wrist fusion apparatus and method which can be used for fusing wrist bones by attachment to a radius and attachment to one or more carpus area bones without attachment to a metacarpal.